Generally, robots are developed for industrial use and widely used in various industrial fields. In recent years, the field of using robots has been expanded to be utilized not only in a medical field, an aerospace field, but also in ordinary households.
A typical example of a robot used at home is a robot cleaner. The robot cleaner performs a function of cleaning an inner space of house by suction impurities such as dust while traveling for itself.
On the other hand, upon performing cleaning, when the robot cleaner reaches a low floor which is lower than an on-going flat ground, such as a living room floor or a cliff, the robot cleaner should change a travel direction to prevent damage due to falling. This is operated by various sensors mounted on the robot cleaner, for example, an infrared sensor and a processor that controls an operation according to a signal received from the sensor.
However, the conventional robot cleaner only uses the infrared sensor to change the travel direction of the robot cleaner and failed to automatically control a suction force according to a type of a floor located below the robot cleaner in operation, such as a hard floor such as a marble, etc. and a soft floor such as a carpet.
Therefore, when the robot cleaner travels on the soft floor in a state in which the robot cleaner operates in a suction mode suitable for the hard floor, there was a problem that cleaning is not properly performed due to low suction force. On the contrary, when the robot cleaner is driven in a state in which the robot clear operates in a suction mode suitable for the soft floor, there was a problem of battery consumption due to the operation a strong suction force even on the hard floor.